Graphic: Key sites in Jacob Wetterling abduction

Police identified Danny Heinrich last October as a "person of interest" in relation to the 1989 abduction of Jacob Wetterling in St. Joseph, Minn. Here's a look at various locations related to the case.

Chloride from de-icers (road salt) and water softeners does not break down in the environment, nor can it be effectively treated, meaning the pollutant builds up in lakes and streams. Here's a look at the flow-adjusted growth in chloride concentrations in rivers near the Twin Cities since 1985.